1. Field of the Invention
The present invention relates to an arm type three-dimensional measuring apparatus and a deflection correction method in the arm type three-dimensional measuring apparatus, and particularly to an arm type three-dimensional measuring apparatus capable of measuring work with high accuracy even when an attitude of a multi-jointed arm mechanism is changed to change a deflection amount in each axis of the multi-jointed arm mechanism during measurement of the work, and a deflection correction method in the arm type three-dimensional measuring apparatus.
2. Description of the Related Art
An arm type three-dimensional measuring apparatus as shown in US 2011/0175745 A1 is used conventionally. This arm type three-dimensional measuring apparatus has a multi-jointed arm mechanism including a probe in the distal end, and a processing part for computing a position of the probe, and is configured to manually move the probe. In other words, this arm type three-dimensional measuring apparatus has a passive configuration in which a driving source is not had in an axis of the multi-jointed arm mechanism.
Also, this arm type three-dimensional measuring apparatus includes plural strain gauges in its arm (link) portion. As a result, such an arm type three-dimensional measuring apparatus can correct a position of the probe by detecting deflection changing by a support method of an operator or an attitude of the multi-jointed arm mechanism based on outputs of the strain gauges.
In recent years, the arm type three-dimensional measuring apparatus has used a lightweight material with small deflection in its arm (link), and has desired to detect and correct deflection in a joint part (concretely, an axis) of the multi-jointed arm mechanism rather than deflection in the link. However, the strain gauges of the arm type three-dimensional measuring apparatus as shown in US 2011/0175745 A1 are configured to detect only the deflection in the link of the multi-jointed arm mechanism, and it was impossible to detect the deflection in the axis.